From mboxrd@z Thu Jan 1 00:00:00 1970 From: Justin Piszcz Subject: Re: stripe_cache_size and performance [BUG with =64kb] Date: Mon, 25 Jun 2007 16:36:25 -0400 (EDT) Message-ID: References: <5d96567b0706211242p7f03bd1cw9102ae3e44d67cee@mail.gmail.com> <5d96567b0706220801v76c1c19cl7448050e62e0860b@mail.gmail.com> <467FF1D5.6080007@tmr.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Bill Davidsen Cc: Raz , jnelson-linux-raid@jamponi.net, linux-raid@vger.kernel.org List-Id: linux-raid.ids On Mon, 25 Jun 2007, Justin Piszcz wrote: > > > On Mon, 25 Jun 2007, Justin Piszcz wrote: > >> >> >> On Mon, 25 Jun 2007, Justin Piszcz wrote: >> >>> >>> >>> On Mon, 25 Jun 2007, Bill Davidsen wrote: >>> >>>> Justin Piszcz wrote: >>>>> I have found a 16MB stripe_cache_size results in optimal performance >>>>> after testing many many values :) >>>> >>>> We have discussed this before, my experience has been that after 8 x >>>> stripe size the performance gains hit diminishing returns, particularly >>>> for typical write instead of big aligned blocks, possibly with O_DIRECT. >>>> I would suggest that as a target even on a low memory machine. >>>> >>>> Do your tests show similar? I was only able to test three and four drive >>>> setups using dedicated drives. >>>> >>>> -- >>>> bill davidsen >>>> CTO TMR Associates, Inc >>>> Doing interesting things with small computers since 1979 >>>> >>>> - >>>> To unsubscribe from this list: send the line "unsubscribe linux-raid" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>>> >>> >>> Running test with 10 RAPTOR 150 hard drives, expect it to take awhile >>> until I get the results, avg them etc. :) >>> >>> 128k,256k,512k,1024k,2048k,4096k,8192k,16384k >>> >>> Justin. >>> >> >> Definitely a kernel bug, I set it to 64kb and it stayed in D-state until I >> ran alt-sysrq-b. >> >> Pretty nasty! >> >> Justin. >> > > Ack, help?? > > [ 64.032895] Starting XFS recovery on filesystem: md3 (logdev: internal) > [ 66.210602] XFS: xlog_recover_process_data: bad clientid > [ 66.210656] XFS: log mount/recovery failed: error 5 > [ 66.210709] XFS: log mount failed > > After I ran 64kb it killed my RAID! > - > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Yeah, I won't be trying that anymore :P p34:/r1# find lost+found/|wc 157 157 3369 p34:/r1# du -sh lost+found/ 166G lost+found/ p34:/r1#